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排序方式: 共有5907条查询结果,搜索用时 274 毫秒
71.
Andrea Pession Maria Grazia Valsecchi Giuseppe Masera Willem A Kamps Edina Magyarosy Carmelo Rizzari Elisabeth R van Wering Luca Lo Nigro Anna van der Does Franco Locatelli Giuseppe Basso Maurizio Aricò 《Journal of clinical oncology》2005,23(28):7161-7167
PURPOSE: Between September 1991 and May 1997, within the International Berlin-Frankfurt-Muenster Study Group (I-BFM-SG), a randomized study was performed aimed at assessing the efficacy of prolonged use of high-dose l-asparaginase (HD-l-ASP) during continuation therapy in children with standard risk (SR) acute lymphoblastic leukemia (ALL), treated with a reduced BFM-type chemotherapy. PATIENTS AND METHODS: The Italian, Dutch, and Hungarian groups participated in this study denominated IDH-ALL-91, and 494 children were enrolled. Treatment consisted of a BFM-type modified backbone with omission of the IB part in induction and elimination of two doses of anthracyclines during reinduction in both arms at the beginning of continuation therapy. Patients were randomly assigned to receive (YES-ASP) or not (NO-ASP) 20 weekly HD-l-ASP (25,000 IU/m2). RESULTS: The event-free-survival and overall survival probabilities at 10 years for the entire group were 82.5% (1.8) and 90.3% (1.3), respectively. Of the 490 patients eligible for random assignment, 355 (72.4%) were randomly assigned (178 YES-ASP and 177 NO-ASP). After a median follow-up of 9 years, the probability of disease-free survival at 10 years was 87.5% (SE, 2.5) for YES-ASP arm versus 78.7% (SE, 3.3) for NO-ASP arm (P = .03). In multivariate analysis, NO-ASP arm (P = .03), male sex (P = .004), and age older than 10 years (P = .0003) had a significantly adverse impact on outcome. CONCLUSION: In this subset of patients, selected with criteria not including monitoring of minimal residual disease, application of extended HD-l-ASP may improve prognosis, compensating reduced leukemia control that results from adoption of a reduced-intensity BFM-backbone for treatment of children with SR ALL. 相似文献
72.
Anabel Pérez-Gómez Armando García-Rodríguez Kevin J James Amaia Ferrero-Gutierrez Antonello Novelli M Teresa Fernández-Sánchez 《Toxicological sciences》2004,80(1):74-82
Diarrhetic shellfish poisoning (DSP) toxins of algal origin are frequent contaminants of coastal waters and seafood. The potential risk for human health due to the continuous presence of these toxins in food has not been clearly established. We have used cerebellar primary cultures to investigate the effects of the DSP toxin dinophysistoxin-2 (DTX-2) on central nervous system neurons and glial cells. Exposure to DTX-2 produced neurotoxicity at concentrations starting at 2.5 nM, characterized first by disintegration of neurites and later by cell death. DTX-2-induced neurodegeneration required long exposures (at least 20 h), involved DNA fragmentation and condensation and fragmentation of chromatin, typical hallmarks of apoptosis, and required the synthesis of new proteins. The concentration that reduced by 50% the maximum neuronal survival after 24 h exposure to DTX-2 (EC50(24)) was approximately 8 nM. Morphology and viability of glial cells remained unaffected up to at least 15 nM DTX-2. Higher concentrations of the toxin caused strong shrinkage of glial cell bodies and retraction of processes, and a significant reduction of glial cell viability. Glial toxicity by DTX-2 involved typical apoptotic condensation and fragmentation of chromatin. Compared to neurons, the effect on glial cells was a much shorter process, and extensive glial degeneration and death occurred after 7 h exposure to DTX-2 (EC50(7) approximately 50 nM; EC50(24) approximately 30 nM). Although further experiments are needed to confirm these toxic actions in vivo, our in vitro data suggest that chronic exposure to amounts of DSP toxins below the current safety regulatory limits may represent a risk for human health that should be taken into consideration. 相似文献
73.
Armando Pérez-Rangel José Manuel Hernández Araceli Castillo-Romero Lilián Yépez-Mulia Rafael Castillo Francisco Hernández-Luis Benjamín Nogueda-Torres Juan Pedro Luna-Arias Gerardo Radilla Gloria León-Avila 《Parasitology research》2013,112(9):3251-3257
In the present study, we evaluated the effect of an albendazole (ABZ) derivative JVG9 on cultured Giardia intestinalis. To assess the JVG9 effects, we evaluated the tubulin cytoskeleton by confocal microscopy, and we found that the characteristic staining was modified. The scanning electron microscopy images revealed extremely damaged trophozoites and cyst-like cells. The confocal images revealed that this drug triggered the expression of cyst wall protein 1 and encystation. We also found that at low doses, AL triggered the encystation process too. 相似文献
74.
75.
Erica de Camargo Ferreira e Vasconcellos Maria Inês Fernandes Pimentel Cláudia Maria Valete-Rosalino Maria de Fátima Madeira Armando de Oliveira Schubach 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):361-362
We report a case of a 42 year-old female, who came to a leishmaniasis
reference center in Rio de Janeiro, Brazil, presenting a cutaneous leishmaniasis
lesion in the right forearm. Treatment with low-dose intramuscular meglumine
antimoniate (MA) (5 mg Sb5+/kg/day) was initiated, with improvement after
28 days, although with the development of generalized eczema. After 87 days, the
lesion worsened. Patient refused treatment with amphotericin B. MA was then
infiltrated in the lesion, in two sessions, resulting in local eczema, with bullae
formation; however, twenty days after, both the ulcer and eczema receded.
Intralesional administration of MA should be used carefully when previous cutaneous
hypersensitivity is detected. 相似文献
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79.
Semantic errors in aphasic patients are frequent and their study has helped understanding the structure and processing of the lexical/semantic system. Most of the patients with semantic errors in reading and writing are English-speaking and it has been argued that this depends on the type of the orthographic systems: in opaque orthographies semantic errors are more frequent than in transparent orthographies. The paper reports the case of an Italian patient, AM, with semantic damage and semantic errors in comprehension and production tasks, except reading aloud. AM was also impaired in non-word repetition and writing but his reading of non-words was only mildly impaired. The absence of semantic errors in reading and the co-occurring absence of severe damage to the non-lexical reading route is consistent with interaction between lexical and non-lexical processing. The discussion addresses the question of the relative frequency of semantic errors in reading and writing tasks in languages with different types of orthographies. 相似文献
80.